March 7 (Reuters) - Serhou Guirassy scored his 12th league goal of the season as Borussia Dortmund kept up their slim hopes of the Bundesliga title with a 2-1 victory over 10-man Cologne on Saturday.

The win takes Dortmund to 55 points from 25 games, 11 points behind leaders Bayern Munich. Cologne are in 13th place with 24 points.

Dortmund took another big step towards Champions League football next season with the victory at RheinEnergieStadion.

Maximilian Beier scored Dortmund's second goal and Cologne lost Jahmai Simpson-Pusey to a straight red card late in the first half, before Jakub Kaminski grabbed a late consolation.

Guirassy scored the opener in the 16th minute when a clearance from Cologne was lifted back into the box by Beier and as the defenders stood and watched, the striker reacted quickest to steer the ball into the back of the net.